Apparatus for compressing and expanding fluids



Oct. 6,. 1931. H. J. Z IMMERMANN APPARATUS FOR COMPRESSING AND EXPANDINGFLUIDS 2 Sheets-Sheet; 1

Filed June 72s. 1928 Fig.2

Fig.1

Oct. 6, 1931. H. J. ZIMMERMANN 1,325,843

APPARATUS FOR COMPRESSING AND EXYANDING FLUIDS 2 Shouts-Sheet 2 FiledJune 23, 1928 Fig Fig.3

Patented Oct. 6, 1931 UNITED STATES HANS JOSEPH ZIMMERMANN, .OFMANNHEIM, GERMANY APPARATUS FOR COMPRESSING AND EXPANDING rLuinsApplication filed June 23, 1928, Serial No. 287,871, and in Germany June25, 1927.

My invention relates to air refrigerating machines under isothermic, orsubstantially isothermic, conditions. To this end I subdivide the volumeof fluid into a plurality of comparatively thin layers and connect eachlayer with a good heat conductor.

For instance, I may secure to the piston head, or to the cylinder head,a plurality of vanes or partitions of metal or other good in which thevanes are secured to the cylinder heat conductor, and provide a volumeof liquid in which the vanes are immersed to a greater or lesser extentduring the complete stroke of the piston. Rapid heat exchange iseffected by subdividing the volume of fluid and by connecting each unitof volume with a good heat conductor, as described.

It has already been suggested in isothermal air compressors to provideheat-exchang ing-means on the piston and on the cylinder head, and aliquid in the cylinder, for the purpose specified, but in thiscompressor separate means are provided for cooling the liquid while inmy invention the liquid itself is relied on for absorbing the heat andfor transferring it to the cylinder walls, or any other part which is incontact with a cooling medium. Obviously, my machine is much simplifiedas compared with the compressor aforesaid by the elimination ofseparatecoolin g means for the liquid and by providing a normal coolingjacket or the like on the cylinder. Besides, my invention relates to airrefrigerating machines, and not to compressors.

Air refrigerating machines heretofore have not been adopted on accountof their poor efficiency. Practically all modern refrigerating machinesare operated on the vapor-compression system in'which the poorefficiency of the-compression is not as important as in airrefrigerating machines. On the other hand, air refrigerating machineshave the good feature that they do not require any chemicals for theiroperation. By operating such machines in accordance with my method, thedrawback of poor eificiency is eliminated and the air refrigeratingmachine is enabled to compete successfully with the vapor-compressionmachine.

In the drawings affixed to this specification and forming part thereof,two types in which my method may be performed, are illustrateddiagrammatically by way of example.

In the drawings, Figs. 1 and 2 are axial sections taken at right anglesto each other throughthe cylinder having vanes secured to its piston, r

Figs. 3 and 4 are' corresponding sections head.

Referring first to Figs. 1 and 2, a is the cylinder, 6 is its piston, 0is its crank, d is its connecting rod, f is a cooling-water jacketsurr'ounding'the' cylinder, 9 is the suction 1 valve and h is thedelivery valve, 21 and hare the suction and delivery passages,respectively, ande are blades or vanes of good heatconductingmaterialsecured to the piston head. The cylinder a'is filledwith liquid to Y,

such a level that in the lower dead centre position of the piston 72some clearance is left between the piston head and the liquid, asrequired. The'length of the vanes 'e. is such that they are permanentlyimmersed in the ,7 liquid duringthecomp'lete stroke of the piston, thatis, theirlower ends must still be immersed in the liquid when the pistonis in its upper dead centre position; 4

Referring now to Figs. 3 and 4, identical parts have been markedwithith'e same reference numerals as in Figs. 1 and 2. In this case thecylinder at is arranged above the crank shaft and the vanes e are notsecured to the piston head but to the cylinder head 1, projectingdownwardly toward the piston. In this instance the liquid is moving withthe piston and itsvolume is such that the vanes Fe remain immersed inthe liquid inany position. The liquid acts as an extensionof' the pistonand care should betaken that clearance be provided between the level ofthe liquidand the cylinder head when the piston b is in the upper deadcentre position.

In operation the fluid which the piston compresses, is broken up into aplurality of comparatively thin layers which rapidly give up their heatto the vanes and to the liquid in which the vanes are permanentlyimmersed.

I Wish it to be understood that various changes may be made in thedetails disclosed in the foregoing specification Without departing fromthe invention or sacrificing the advantages thereof.

I claim:

1. Inian-aircompressing machine, the combination of a cylinder, a pistonadapted to reciprocate in said cylinder, partitions of heat-conductingmaterial subdividing the space of said cylinder into a plurality ofchambers, and means for cooling said cylinder on the outside.

2. In an air compressing machine, the combination of a cylinder, apiston adapted to reciprocate in said cylinder, partitions of heatconducting material on said pistoufor subdividing the space of saidcylinder into a plurality of chambers, andmeans for cooling saidcylinder on the outside.

3. In an air compressing machine. the combination of a cylinder, apiston adapted to reciprocate in said cylinder, partitions ofheaticonducting material in said cylinder for subdividing the space ofsaid cylinder into a plurality of chambers, and means for cooling saidcylinder on the outside.

4'. In an air compressing machine, the combinnvion ofa'verticalcylinder, a piston adapted to reciprocate in said cylinder, a body ofliquid at thebottom of said cylinder. heatconducting means on the bottomof said pistun adapted to move within said body of liquid while saidpiston reciprocates, and means for cooling said cylinder on the outside.

5i In an air compressing machine, the combination of a vertical invertedcylinder. a pistonadapted'to reciprocate in said cylinder, a body ofliquid supported by, and reciproeating with said piston, the volume ofsaid being so determined'as to compress air between the liquid and thebottom of said cylinder, and meansfor cooling said cylinder on' theoutside.

6. 11mm air compressing machine, the combination of a verticalinvertedcylinder, a piston adapted to reciprocate in said cylinder.heat-conducting means on the bottom of said cylinder, a body of liquidsupported by and reciprocatingwith' said piston while in contact withsaid heat-conducting means, the volumeofsaidhody being so determined asto compress air between the liquid and the bottom of'said cylinder, andmeans for cooling said cylinder on the outside.

In'testimony whereof I aflix my signature.

HANS JOSEPH ZIMMERMANN.

